/*******************************************************************************
 * Copyright (c) 2000, 2005 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.draw2d;

import org.eclipse.draw2d.geometry.Dimension;
import org.eclipse.draw2d.geometry.Rectangle;
import org.eclipse.draw2d.geometry.Translatable;

/**
 * A non-freeform, scalable layered pane.  
 * @author Eric Bordeau
 * @since 2.1.1
 */
public class ScalableLayeredPane 
	extends LayeredPane 
	implements ScalableFigure
{

private double scale = 1.0;

/**
 * @see IFigure#getClientArea_1(Rectangle)
 */
public Rectangle getClientArea_1(Rectangle rect) {
	super.getClientArea_1(rect);
	rect.width /= scale;
	rect.height /= scale;
	rect.x /= scale;
	rect.y /= scale;
	return rect;
}

/**
 * @see Figure#getPreferredSize_1(int, int)
 */
public Dimension getMinimumSize(int wHint, int hHint) {
	Dimension d = super.getMinimumSize((int) (wHint / getScale()), (int)(hHint / getScale()));
	int w = getInsets().getWidth();
	int h = getInsets().getHeight();
	return d.getExpanded(-w, -h)
		.scale_0(scale)
		.expand(w, h);
}

/**
 * @see Figure#getPreferredSize_1(int, int)
 */
public Dimension getPreferredSize_1(int wHint, int hHint) {
	Dimension d = super.getPreferredSize_1((int) (wHint / getScale()), (int)(hHint / getScale()));
	int w = getInsets().getWidth();
	int h = getInsets().getHeight();
	return d.getExpanded(-w, -h)
		.scale_0(scale)
		.expand(w, h);
}

/**
 * Returns the scale level, default is 1.0.
 * @return the scale level
 */
public double getScale() {
	return scale;
}

/**
 * @see org.eclipse.draw2d.IFigure#isCoordinateSystem()
 */
public boolean isCoordinateSystem() {
	return true;
}

/**
 * @see org.eclipse.draw2d.Figure#paintClientArea(Graphics)
 */
protected void paintClientArea(Graphics graphics) {
	if (getChildren().isEmpty())
		return;
	if (scale == 1.0) {
		super.paintClientArea(graphics);
	} else {
		ScaledGraphics g = new ScaledGraphics(graphics);
		boolean optimizeClip = getBorder() == null || getBorder().isOpaque();
		if (!optimizeClip)
			g.clipRect(getBounds().getCropped(getInsets()));
		g.scale(scale);
		g.pushState();
		paintChildren(g);
		g.dispose();
		graphics.restoreState();
	}
}

/**
 * Sets the zoom level
 * @param newZoom The new zoom level
 */
public void setScale(double newZoom) {
	if (scale == newZoom)
		return;
	scale = newZoom;
	fireMoved(); //for AncestorListener compatibility
	revalidate();
	repaint_0();
}

/**
 * @see org.eclipse.draw2d.Figure#translateFromParent(Translatable)
 */
public void translateFromParent(Translatable t) {
	t.performScale(1 / scale);
}

/**
 * @see org.eclipse.draw2d.Figure#translateToParent(Translatable)
 */
public void translateToParent(Translatable t) {
	t.performScale(scale);
}

}
